FormKeep will accept any data as a standard html post request and save the values into our database, and then send the info to the configured notifications like email or other services. We don’t have an authentication layer on top of that. If you’re trying to restrict who can submit information from the html form we don’t have a way to handle that ourselves, but you can gate the actual form in any fashion you want.
Many of our customers don’t use our form designer and build their own forms with features like authentication or validation before posting the data to us. In this case we’re more of a form backend service.